30 lines
1.2 KiB
Markdown
30 lines
1.2 KiB
Markdown
---
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title: elementIsVisibleInViewport
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tags: browser,intermediate
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firstSeen: 2017-12-17T17:55:51+02:00
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lastUpdated: 2020-10-22T20:23:47+03:00
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---
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Checks if the element specified is visible in the viewport.
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- Use `Element.getBoundingClientRect()` and the `Window.inner(Width|Height)` values to determine if a given element is visible in the viewport.
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- Omit the second argument to determine if the element is entirely visible, or specify `true` to determine if it is partially visible.
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```js
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const elementIsVisibleInViewport = (el, partiallyVisible = false) => {
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const { top, left, bottom, right } = el.getBoundingClientRect();
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const { innerHeight, innerWidth } = window;
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return partiallyVisible
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? ((top > 0 && top < innerHeight) ||
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(bottom > 0 && bottom < innerHeight)) &&
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((left > 0 && left < innerWidth) || (right > 0 && right < innerWidth))
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: top >= 0 && left >= 0 && bottom <= innerHeight && right <= innerWidth;
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};
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```
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```js
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// e.g. 100x100 viewport and a 10x10px element at position {top: -1, left: 0, bottom: 9, right: 10}
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elementIsVisibleInViewport(el); // false - (not fully visible)
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elementIsVisibleInViewport(el, true); // true - (partially visible)
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```
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